Child with a Heterozygous Deletion of 2 Megabases that Includes the DAG1 Gene, Presenting as Developmental Delay

Abstract

The role of dystroglycan in neuromuscular disease is complex and not well understood. Mutations in the human dystroglycan gene itself have only rarely been reported to be associated with clinical semiology. We report on a child with developmental delay who was found to have a deletion of 3p.21.31 to p21.2 of approximately 2.1 megabases—a rare presentation probably due to a dystrophin-associated glycoprotein 1 (DAG1) gene mutation. In addition, she had mild calf muscle hypertrophy, mildly elevated creatine phosphokinase, abnormal muscle biopsy with reduced α dystroglycan staining, neuroimaging abnormalities in the form of white matter hyperintensities, and electroencephalography with epileptiform activity. Our case report adds to the literature on the functional consequence and phenotypic spectrum associated with a primary dystroglycanopathy due to a DAG1 mutation.

Keywords

DAG1 gene mutation - developmental delay - raised creatine phosphokinase - MRI - brain abnormality - epileptiform EEG

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